as.Date("2022-08-22")
[1] "2022-08-22"
POSIX - Start at 1970-01-01 00:00:00
date_time1 <- as.POSIXct("2020-01-01 00:00:00")
date_time1
[1] "2020-01-01 GMT"
unclass(date_time1)
[1] 1577836800
attr(,"tzone")
[1] ""
This returns the number of seconds that have passed between 1970-01-01 [(38 * 365) + (12 * 366)] * 24 * 60 * 60 = 1577836800
date_time2 <- as.POSIXlt("2020-01-01 00:00:00")
date_time2
[1] "2020-01-01 GMT"
unclass(date_time2)
$sec
[1] 0
$min
[1] 0
$hour
[1] 0
$mday
[1] 1
$mon
[1] 0
$year
[1] 120
$wday
[1] 3
$yday
[1] 0
$isdst
[1] 0
$zone
[1] "GMT"
$gmtoff
[1] NA
library(tidyverse)
Registered S3 methods overwritten by 'dbplyr':
method from
print.tbl_lazy
print.tbl_sql
── Attaching packages ───────────────────────────────────────────────────────────────────────────────────────────────────────────────────── tidyverse 1.3.1 ──
✔ ggplot2 3.3.6 ✔ purrr 0.3.4
✔ tibble 3.1.7 ✔ dplyr 1.0.9
✔ tidyr 1.2.0 ✔ stringr 1.4.0
✔ readr 2.1.2 ✔ forcats 0.5.1
── Conflicts ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── tidyverse_conflicts() ──
✖ dplyr::filter() masks stats::filter()
✖ dplyr::lag() masks stats::lag()
library(lubridate)
Attaching package: ‘lubridate’
The following objects are masked from ‘package:base’:
date, intersect, setdiff, union
netflix <- read_csv("data/netflix.csv")
Rows: 7787 Columns: 12
── Column specification ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
Delimiter: ","
chr (11): show_id, type, title, director, cast, country, date_added, rating, duration, listed_in, description
dbl (1): release_year
ℹ Use `spec()` to retrieve the full column specification for this data.
ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
ymd_h("2019-01-19 10")
[1] "2019-01-19 10:00:00 UTC"
netflix <- netflix %>%
mutate(date_added = mdy(date_added))
netflix
Difftime: a datetime object that represents
days Period: represent a timespan e.g. week/month/day
Duration: represent an exact number of seconds
netflix <- netflix %>%
mutate(time_duration = as.duration(today() - date_added))
netflix %>%
select(starts_with("time_"))
OlsonNames()
[1] "Africa/Abidjan" "Africa/Accra" "Africa/Addis_Ababa"
[4] "Africa/Algiers" "Africa/Asmara" "Africa/Asmera"
[7] "Africa/Bamako" "Africa/Bangui" "Africa/Banjul"
[10] "Africa/Bissau" "Africa/Blantyre" "Africa/Brazzaville"
[13] "Africa/Bujumbura" "Africa/Cairo" "Africa/Casablanca"
[16] "Africa/Ceuta" "Africa/Conakry" "Africa/Dakar"
[19] "Africa/Dar_es_Salaam" "Africa/Djibouti" "Africa/Douala"
[22] "Africa/El_Aaiun" "Africa/Freetown" "Africa/Gaborone"
[25] "Africa/Harare" "Africa/Johannesburg" "Africa/Juba"
[28] "Africa/Kampala" "Africa/Khartoum" "Africa/Kigali"
[31] "Africa/Kinshasa" "Africa/Lagos" "Africa/Libreville"
[34] "Africa/Lome" "Africa/Luanda" "Africa/Lubumbashi"
[37] "Africa/Lusaka" "Africa/Malabo" "Africa/Maputo"
[40] "Africa/Maseru" "Africa/Mbabane" "Africa/Mogadishu"
[43] "Africa/Monrovia" "Africa/Nairobi" "Africa/Ndjamena"
[46] "Africa/Niamey" "Africa/Nouakchott" "Africa/Ouagadougou"
[49] "Africa/Porto-Novo" "Africa/Sao_Tome" "Africa/Timbuktu"
[52] "Africa/Tripoli" "Africa/Tunis" "Africa/Windhoek"
[55] "America/Adak" "America/Anchorage" "America/Anguilla"
[58] "America/Antigua" "America/Araguaina" "America/Argentina/Buenos_Aires"
[61] "America/Argentina/Catamarca" "America/Argentina/ComodRivadavia" "America/Argentina/Cordoba"
[64] "America/Argentina/Jujuy" "America/Argentina/La_Rioja" "America/Argentina/Mendoza"
[67] "America/Argentina/Rio_Gallegos" "America/Argentina/Salta" "America/Argentina/San_Juan"
[70] "America/Argentina/San_Luis" "America/Argentina/Tucuman" "America/Argentina/Ushuaia"
[73] "America/Aruba" "America/Asuncion" "America/Atikokan"
[76] "America/Atka" "America/Bahia" "America/Bahia_Banderas"
[79] "America/Barbados" "America/Belem" "America/Belize"
[82] "America/Blanc-Sablon" "America/Boa_Vista" "America/Bogota"
[85] "America/Boise" "America/Buenos_Aires" "America/Cambridge_Bay"
[88] "America/Campo_Grande" "America/Cancun" "America/Caracas"
[91] "America/Catamarca" "America/Cayenne" "America/Cayman"
[94] "America/Chicago" "America/Chihuahua" "America/Coral_Harbour"
[97] "America/Cordoba" "America/Costa_Rica" "America/Creston"
[100] "America/Cuiaba" "America/Curacao" "America/Danmarkshavn"
[103] "America/Dawson" "America/Dawson_Creek" "America/Denver"
[106] "America/Detroit" "America/Dominica" "America/Edmonton"
[109] "America/Eirunepe" "America/El_Salvador" "America/Ensenada"
[112] "America/Fort_Nelson" "America/Fort_Wayne" "America/Fortaleza"
[115] "America/Glace_Bay" "America/Godthab" "America/Goose_Bay"
[118] "America/Grand_Turk" "America/Grenada" "America/Guadeloupe"
[121] "America/Guatemala" "America/Guayaquil" "America/Guyana"
[124] "America/Halifax" "America/Havana" "America/Hermosillo"
[127] "America/Indiana/Indianapolis" "America/Indiana/Knox" "America/Indiana/Marengo"
[130] "America/Indiana/Petersburg" "America/Indiana/Tell_City" "America/Indiana/Vevay"
[133] "America/Indiana/Vincennes" "America/Indiana/Winamac" "America/Indianapolis"
[136] "America/Inuvik" "America/Iqaluit" "America/Jamaica"
[139] "America/Jujuy" "America/Juneau" "America/Kentucky/Louisville"
[142] "America/Kentucky/Monticello" "America/Knox_IN" "America/Kralendijk"
[145] "America/La_Paz" "America/Lima" "America/Los_Angeles"
[148] "America/Louisville" "America/Lower_Princes" "America/Maceio"
[151] "America/Managua" "America/Manaus" "America/Marigot"
[154] "America/Martinique" "America/Matamoros" "America/Mazatlan"
[157] "America/Mendoza" "America/Menominee" "America/Merida"
[160] "America/Metlakatla" "America/Mexico_City" "America/Miquelon"
[163] "America/Moncton" "America/Monterrey" "America/Montevideo"
[166] "America/Montreal" "America/Montserrat" "America/Nassau"
[169] "America/New_York" "America/Nipigon" "America/Nome"
[172] "America/Noronha" "America/North_Dakota/Beulah" "America/North_Dakota/Center"
[175] "America/North_Dakota/New_Salem" "America/Nuuk" "America/Ojinaga"
[178] "America/Panama" "America/Pangnirtung" "America/Paramaribo"
[181] "America/Phoenix" "America/Port_of_Spain" "America/Port-au-Prince"
[184] "America/Porto_Acre" "America/Porto_Velho" "America/Puerto_Rico"
[187] "America/Punta_Arenas" "America/Rainy_River" "America/Rankin_Inlet"
[190] "America/Recife" "America/Regina" "America/Resolute"
[193] "America/Rio_Branco" "America/Rosario" "America/Santa_Isabel"
[196] "America/Santarem" "America/Santiago" "America/Santo_Domingo"
[199] "America/Sao_Paulo" "America/Scoresbysund" "America/Shiprock"
[202] "America/Sitka" "America/St_Barthelemy" "America/St_Johns"
[205] "America/St_Kitts" "America/St_Lucia" "America/St_Thomas"
[208] "America/St_Vincent" "America/Swift_Current" "America/Tegucigalpa"
[211] "America/Thule" "America/Thunder_Bay" "America/Tijuana"
[214] "America/Toronto" "America/Tortola" "America/Vancouver"
[217] "America/Virgin" "America/Whitehorse" "America/Winnipeg"
[220] "America/Yakutat" "America/Yellowknife" "Antarctica/Casey"
[223] "Antarctica/Davis" "Antarctica/DumontDUrville" "Antarctica/Macquarie"
[226] "Antarctica/Mawson" "Antarctica/McMurdo" "Antarctica/Palmer"
[229] "Antarctica/Rothera" "Antarctica/South_Pole" "Antarctica/Syowa"
[232] "Antarctica/Troll" "Antarctica/Vostok" "Arctic/Longyearbyen"
[235] "Asia/Aden" "Asia/Almaty" "Asia/Amman"
[238] "Asia/Anadyr" "Asia/Aqtau" "Asia/Aqtobe"
[241] "Asia/Ashgabat" "Asia/Ashkhabad" "Asia/Atyrau"
[244] "Asia/Baghdad" "Asia/Bahrain" "Asia/Baku"
[247] "Asia/Bangkok" "Asia/Barnaul" "Asia/Beirut"
[250] "Asia/Bishkek" "Asia/Brunei" "Asia/Calcutta"
[253] "Asia/Chita" "Asia/Choibalsan" "Asia/Chongqing"
[256] "Asia/Chungking" "Asia/Colombo" "Asia/Dacca"
[259] "Asia/Damascus" "Asia/Dhaka" "Asia/Dili"
[262] "Asia/Dubai" "Asia/Dushanbe" "Asia/Famagusta"
[265] "Asia/Gaza" "Asia/Harbin" "Asia/Hebron"
[268] "Asia/Ho_Chi_Minh" "Asia/Hong_Kong" "Asia/Hovd"
[271] "Asia/Irkutsk" "Asia/Istanbul" "Asia/Jakarta"
[274] "Asia/Jayapura" "Asia/Jerusalem" "Asia/Kabul"
[277] "Asia/Kamchatka" "Asia/Karachi" "Asia/Kashgar"
[280] "Asia/Kathmandu" "Asia/Katmandu" "Asia/Khandyga"
[283] "Asia/Kolkata" "Asia/Krasnoyarsk" "Asia/Kuala_Lumpur"
[286] "Asia/Kuching" "Asia/Kuwait" "Asia/Macao"
[289] "Asia/Macau" "Asia/Magadan" "Asia/Makassar"
[292] "Asia/Manila" "Asia/Muscat" "Asia/Nicosia"
[295] "Asia/Novokuznetsk" "Asia/Novosibirsk" "Asia/Omsk"
[298] "Asia/Oral" "Asia/Phnom_Penh" "Asia/Pontianak"
[301] "Asia/Pyongyang" "Asia/Qatar" "Asia/Qostanay"
[304] "Asia/Qyzylorda" "Asia/Rangoon" "Asia/Riyadh"
[307] "Asia/Saigon" "Asia/Sakhalin" "Asia/Samarkand"
[310] "Asia/Seoul" "Asia/Shanghai" "Asia/Singapore"
[313] "Asia/Srednekolymsk" "Asia/Taipei" "Asia/Tashkent"
[316] "Asia/Tbilisi" "Asia/Tehran" "Asia/Tel_Aviv"
[319] "Asia/Thimbu" "Asia/Thimphu" "Asia/Tokyo"
[322] "Asia/Tomsk" "Asia/Ujung_Pandang" "Asia/Ulaanbaatar"
[325] "Asia/Ulan_Bator" "Asia/Urumqi" "Asia/Ust-Nera"
[328] "Asia/Vientiane" "Asia/Vladivostok" "Asia/Yakutsk"
[331] "Asia/Yangon" "Asia/Yekaterinburg" "Asia/Yerevan"
[334] "Atlantic/Azores" "Atlantic/Bermuda" "Atlantic/Canary"
[337] "Atlantic/Cape_Verde" "Atlantic/Faeroe" "Atlantic/Faroe"
[340] "Atlantic/Jan_Mayen" "Atlantic/Madeira" "Atlantic/Reykjavik"
[343] "Atlantic/South_Georgia" "Atlantic/St_Helena" "Atlantic/Stanley"
[346] "Australia/ACT" "Australia/Adelaide" "Australia/Brisbane"
[349] "Australia/Broken_Hill" "Australia/Canberra" "Australia/Currie"
[352] "Australia/Darwin" "Australia/Eucla" "Australia/Hobart"
[355] "Australia/LHI" "Australia/Lindeman" "Australia/Lord_Howe"
[358] "Australia/Melbourne" "Australia/North" "Australia/NSW"
[361] "Australia/Perth" "Australia/Queensland" "Australia/South"
[364] "Australia/Sydney" "Australia/Tasmania" "Australia/Victoria"
[367] "Australia/West" "Australia/Yancowinna" "Brazil/Acre"
[370] "Brazil/DeNoronha" "Brazil/East" "Brazil/West"
[373] "Canada/Atlantic" "Canada/Central" "Canada/Eastern"
[376] "Canada/Mountain" "Canada/Newfoundland" "Canada/Pacific"
[379] "Canada/Saskatchewan" "Canada/Yukon" "CET"
[382] "Chile/Continental" "Chile/EasterIsland" "CST6CDT"
[385] "Cuba" "EET" "Egypt"
[388] "Eire" "EST" "EST5EDT"
[391] "Etc/GMT" "Etc/GMT-0" "Etc/GMT-1"
[394] "Etc/GMT-10" "Etc/GMT-11" "Etc/GMT-12"
[397] "Etc/GMT-13" "Etc/GMT-14" "Etc/GMT-2"
[400] "Etc/GMT-3" "Etc/GMT-4" "Etc/GMT-5"
[403] "Etc/GMT-6" "Etc/GMT-7" "Etc/GMT-8"
[406] "Etc/GMT-9" "Etc/GMT+0" "Etc/GMT+1"
[409] "Etc/GMT+10" "Etc/GMT+11" "Etc/GMT+12"
[412] "Etc/GMT+2" "Etc/GMT+3" "Etc/GMT+4"
[415] "Etc/GMT+5" "Etc/GMT+6" "Etc/GMT+7"
[418] "Etc/GMT+8" "Etc/GMT+9" "Etc/GMT0"
[421] "Etc/Greenwich" "Etc/UCT" "Etc/Universal"
[424] "Etc/UTC" "Etc/Zulu" "Europe/Amsterdam"
[427] "Europe/Andorra" "Europe/Astrakhan" "Europe/Athens"
[430] "Europe/Belfast" "Europe/Belgrade" "Europe/Berlin"
[433] "Europe/Bratislava" "Europe/Brussels" "Europe/Bucharest"
[436] "Europe/Budapest" "Europe/Busingen" "Europe/Chisinau"
[439] "Europe/Copenhagen" "Europe/Dublin" "Europe/Gibraltar"
[442] "Europe/Guernsey" "Europe/Helsinki" "Europe/Isle_of_Man"
[445] "Europe/Istanbul" "Europe/Jersey" "Europe/Kaliningrad"
[448] "Europe/Kiev" "Europe/Kirov" "Europe/Lisbon"
[451] "Europe/Ljubljana" "Europe/London" "Europe/Luxembourg"
[454] "Europe/Madrid" "Europe/Malta" "Europe/Mariehamn"
[457] "Europe/Minsk" "Europe/Monaco" "Europe/Moscow"
[460] "Europe/Nicosia" "Europe/Oslo" "Europe/Paris"
[463] "Europe/Podgorica" "Europe/Prague" "Europe/Riga"
[466] "Europe/Rome" "Europe/Samara" "Europe/San_Marino"
[469] "Europe/Sarajevo" "Europe/Saratov" "Europe/Simferopol"
[472] "Europe/Skopje" "Europe/Sofia" "Europe/Stockholm"
[475] "Europe/Tallinn" "Europe/Tirane" "Europe/Tiraspol"
[478] "Europe/Ulyanovsk" "Europe/Uzhgorod" "Europe/Vaduz"
[481] "Europe/Vatican" "Europe/Vienna" "Europe/Vilnius"
[484] "Europe/Volgograd" "Europe/Warsaw" "Europe/Zagreb"
[487] "Europe/Zaporozhye" "Europe/Zurich" "Factory"
[490] "GB" "GB-Eire" "GMT"
[493] "GMT-0" "GMT+0" "GMT0"
[496] "Greenwich" "Hongkong" "HST"
[499] "Iceland" "Indian/Antananarivo" "Indian/Chagos"
[502] "Indian/Christmas" "Indian/Cocos" "Indian/Comoro"
[505] "Indian/Kerguelen" "Indian/Mahe" "Indian/Maldives"
[508] "Indian/Mauritius" "Indian/Mayotte" "Indian/Reunion"
[511] "Iran" "Israel" "Jamaica"
[514] "Japan" "Kwajalein" "Libya"
[517] "MET" "Mexico/BajaNorte" "Mexico/BajaSur"
[520] "Mexico/General" "MST" "MST7MDT"
[523] "Navajo" "NZ" "NZ-CHAT"
[526] "Pacific/Apia" "Pacific/Auckland" "Pacific/Bougainville"
[529] "Pacific/Chatham" "Pacific/Chuuk" "Pacific/Easter"
[532] "Pacific/Efate" "Pacific/Enderbury" "Pacific/Fakaofo"
[535] "Pacific/Fiji" "Pacific/Funafuti" "Pacific/Galapagos"
[538] "Pacific/Gambier" "Pacific/Guadalcanal" "Pacific/Guam"
[541] "Pacific/Honolulu" "Pacific/Johnston" "Pacific/Kiritimati"
[544] "Pacific/Kosrae" "Pacific/Kwajalein" "Pacific/Majuro"
[547] "Pacific/Marquesas" "Pacific/Midway" "Pacific/Nauru"
[550] "Pacific/Niue" "Pacific/Norfolk" "Pacific/Noumea"
[553] "Pacific/Pago_Pago" "Pacific/Palau" "Pacific/Pitcairn"
[556] "Pacific/Pohnpei" "Pacific/Ponape" "Pacific/Port_Moresby"
[559] "Pacific/Rarotonga" "Pacific/Saipan" "Pacific/Samoa"
[562] "Pacific/Tahiti" "Pacific/Tarawa" "Pacific/Tongatapu"
[565] "Pacific/Truk" "Pacific/Wake" "Pacific/Wallis"
[568] "Pacific/Yap" "Poland" "Portugal"
[571] "PRC" "PST8PDT" "ROC"
[574] "ROK" "Singapore" "Turkey"
[577] "UCT" "Universal" "US/Alaska"
[580] "US/Aleutian" "US/Arizona" "US/Central"
[583] "US/East-Indiana" "US/Eastern" "US/Hawaii"
[586] "US/Indiana-Starke" "US/Michigan" "US/Mountain"
[589] "US/Pacific" "US/Samoa" "UTC"
[592] "W-SU" "WET" "Zulu"
attr(,"Version")
[1] "2021a"
ymd_hms("2023-09-13 10:22:01", tz = "Atlantic/Faeroe")
[1] "2023-09-13 10:22:01 WEST"
netflix %>%
mutate(date_tz_1 = force_tz(date_added, tzone = "Asia/Singapore"),
date_tz_2 = with_tz(date_added, tzone = "Asia/Singapore")) %>%
select(date_added, date_tz_1, date_tz_2)